JS Help

[WARlrus]

Hi, I have made the following script (hybrid version of a couple of widely available scripts)

This script is supposed to allow the div "alert" to be dragged arond, but the AJAX request is a script that displays "alert" only when there is some content to be displayed.

index.php is:

<script>
function HideContent(d) {
if(d.length < 1) { return; }
document.getElementById(d).style.display = "none";
}
function ShowContent(d) {
if(d.length < 1) { return; }
document.getElementById(d).style.display = "";
}

// Get base url
url = document.location.href;
xend = url.lastIndexOf("/") + 1;
var base_url = url.substring(0, xend);

function ajax_do (url) {
// Does URL begin with http?
if (url.substring(0, 4) != 'http') {
url = base_url + url;
}

// Create new JS element
var jsel = document.createElement('SCRIPT');
jsel.type = 'text/javascript';
jsel.src = url;

// Append JS element (therefore executing the 'AJAX' call)
document.body.appendChild (jsel);
}

//*****************************************************************************
// Do not remove this notice.
//
// Copyright 2001 by Mike Hall.
// See http://www.brainjar.com for terms of use.
//*****************************************************************************

// Determine browser and version.

function Browser() {

var ua, s, i;

this.isIE = false;
this.isNS = false;
this.version = null;

ua = navigator.userAgent;

s = "MSIE";
if ((i = ua.indexOf(s)) >= 0) {
this.isIE = true;
this.version = parseFloat(ua.substr(i + s.length));
return;
}

s = "Netscape6/";
if ((i = ua.indexOf(s)) >= 0) {
this.isNS = true;
this.version = parseFloat(ua.substr(i + s.length));
return;
}

// Treat any other "Gecko" browser as NS 6.1.

s = "Gecko";
if ((i = ua.indexOf(s)) >= 0) {
this.isNS = true;
this.version = 6.1;
return;
}
}

var browser = new Browser();

// Global object to hold drag information.

var dragObj = new Object();
dragObj.zIndex = 0;

function dragStart(event, id) {

var el;
var x, y;

// If an element id was given, find it. Otherwise use the element being
// clicked on.

if (id)
dragObj.elNode = document.getElementById(id);
else {
if (browser.isIE)
dragObj.elNode = window.event.srcElement;
if (browser.isNS)
dragObj.elNode = event.target;

// If this is a text node, use its parent element.

if (dragObj.elNode.nodeType == 3)
dragObj.elNode = dragObj.elNode.parentNode;
}

// Get cursor position with respect to the page.

if (browser.isIE) {
x = window.event.clientX + document.documentElement.scrollLeft
+ document.body.scrollLeft;
y = window.event.clientY + document.documentElement.scrollTop
+ document.body.scrollTop;
}
if (browser.isNS) {
x = event.clientX + window.scrollX;
y = event.clientY + window.scrollY;
}

// Save starting positions of cursor and element.

dragObj.cursorStartX = x;
dragObj.cursorStartY = y;
dragObj.elStartLeft = parseInt(dragObj.elNode.style.left, 10);
dragObj.elStartTop = parseInt(dragObj.elNode.style.top, 10);

if (isNaN(dragObj.elStartLeft)) dragObj.elStartLeft = 0;
if (isNaN(dragObj.elStartTop)) dragObj.elStartTop = 0;

// Update element's z-index.

dragObj.elNode.style.zIndex = ++dragObj.zIndex;

// Capture mousemove and mouseup events on the page.

if (browser.isIE) {
document.attachEvent("onmousemove", dragGo);
document.attachEvent("onmouseup", dragStop);
window.event.cancelBubble = true;
window.event.returnValue = false;
}
if (browser.isNS) {
document.addEventListener("mousemove", dragGo, true);
document.addEventListener("mouseup", dragStop, true);
event.preventDefault();
}
}

function dragGo(event) {

var x, y;

// Get cursor position with respect to the page.

if (browser.isIE) {
x = window.event.clientX + document.documentElement.scrollLeft
+ document.body.scrollLeft;
y = window.event.clientY + document.documentElement.scrollTop
+ document.body.scrollTop;
}
if (browser.isNS) {
x = event.clientX + window.scrollX;
y = event.clientY + window.scrollY;
}

// Move drag element by the same amount the cursor has moved.

dragObj.elNode.style.left = (dragObj.elStartLeft + x - dragObj.cursorStartX) + "px";
dragObj.elNode.style.top = (dragObj.elStartTop + y - dragObj.cursorStartY) + "px";

if (browser.isIE) {
window.event.cancelBubble = true;
window.event.returnValue = false;
}
if (browser.isNS)
event.preventDefault();
}

function dragStop(event) {

// Stop capturing mousemove and mouseup events.

if (browser.isIE) {
document.detachEvent("onmousemove", dragGo);
document.detachEvent("onmouseup", dragStop);
}
if (browser.isNS) {
document.removeEventListener("mousemove", dragGo, true);
document.removeEventListener("mouseup", dragStop, true);
}
}

//]]>
</script>
<html>
<head>
<title>Untitled Document</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
</head>

<body>
<div title="alert" id="alert">
<table border="0" cellpadding="0" cellspacing="0">
<tr>
<td><div id="drag" onmousedown="dragStart(event,'alert')"><img src="top.gif" width="400" height="37" border="0" usemap="#Map"></div></td>
</tr>
<tr>
<td background="row.gif">
<table width="367" border="0" align="center">
<tr>
<td><div id="contentdiv"></div>
</td>
</tr>
</table></td>
</tr>
<tr>
<td><img src="bottom.gif" width="400" height="18"></td>
</tr>
</table>
</div>
<script>HideContent('alert')</script>
<map name="Map">
<area shape="rect" coords="371,5,384,19" href="javascript:HideContent('alert')">
</map>
</body>
</html>

(Apologies for posting full thing, the problem may be anywhere!)

and page1.php is:


<?php

$html = 'This content is grabbed from the server';

if($html)
{
?>

div = document.getElementById('contentdiv');
div.innerHTML = '<?php echo $html; ?>';

document.getElementById('alert').style.display = "";

<?
}
?>


I have 2 problems with this:

1) The box will not drag around
2) I cannot figure out how to get the AJAX request to be sent every 30 seconds, as I wish the script to do this.

Any help/pointers would be greatly appreciated!